Solenoid



Aug. 22, 1944. M. w. BOWEN SOLENOID Filed Nov. 6, 1942 INVENTOB B MY/80N W. BOWEN TORNEYS I Patented Aug. 22, 1944 SOLENOID Myron W. Bowen, Niles, Mlcht, assignor to Bendix Home Appliances, Inn, South, Bend, 11111., a corporation of Delaware Application November 6, 1942, Serial No. 464,931

1 Claim.

This invention relates solenoids.

Solenoids of the type here illustrated are intended to be energized with alternating current and used for the purpose of the remote control of valves, switches, belt shifters, or am other equipment requiring a moderate amount of work in its operation.

The object of this invention is to increase the pull of the armature of the solenoid structure at intermediate points in its stroke by lessening the air gap between the iron of the solenoid armature and the internal coil of the solenoid winding without decreasing the effecting amount of iron of the armature lying adjacent the internal coil of the exciting winding.

Solenoids of the general class here illustrated are provided with a non-magnetic guide for the armature, which guide constitutes a frame about which the exciting winding is assembled. It is important that the armature be provided with a stop to prevent its complete withdrawal from the magnetic frame and that the'two stops, one carried by the armature and the other by the frame, which engage one another at the outer edge of the armature stroke must be very substantial to prevent them from being distorted and eventually broken by continuous hammering.

' One method heretofore proposed for securing an adequate stop was to provide a slot in the side of the armature and a cooperating pin in the frame. An objection to this construction is that if the slot in the armature is made large enough for the abutment projecting into it to have adequate strength, the magnetic section of the armature is decreased and the pull consequently lessened. Another form of stop heretofore used comprised extending a pin carried by the armature entirely through a slot in the armature guide frame so that it can abut a cross member lying outside the plane of the outside wall of the armature guide frame. Such an arrangement requires a space between the guide member and the inner coil of the operating winding with a consequent loss of power.

In accordance with the present invention, a pin extends across the armature at its inner end and is provided with thin washers adjacent the armature, but not thick enough to extend entirely through the slots provided along the metal forming the armature guide. The outer end of the armature guide metal is bent away from the armature to receive abutments in the form of thin plates having parts formed to the same contours as the washers carried by the armature. This structure makes it possible to reduce the air gap between the armature and the inner coil of the exciting winding without reducing the cross section of the armature. The armature pull is thus materially increased and the heat losses from hysteresis are materially decreased.

My invention is illustrated in the accompanying drawing in which,'

Fig. 1 is an isometric view of an assembled solenoid with the armature protruding p rt way out of the c-shaped held. 4

Fig. 2 is a horizontal section through the armature and field showing the stops in unregistering position.

Fig. 3 is a perspective view of the armature guide with armature and armature stop members assembled therein.

Fig. 4 is a perspective of one of the sections of the non-magnetic armature guide, and

Fig. 5 is a perspective of one of the stop plates for the armature.

The field of the solenoid comprises a plurality of C-shaped laminations I 0 secured together by transverse fastening devices Ii here shown as rivets. Two armature guide members ll of nonmagnetic material extend across the magnetic fleld and through the 0 opening of the field. A winding l5 of insulated magnet wire having a rectangular opening therethroush surrounds the guides I 3 with its inner coil lying adjacent thereto. In order to assemble the winding II within the field Ill the coil is placed in position within the c-shaped field and the armature guide parts I 3 are inserted through the C opening of the magnetic field and through the rectangular opening within the coil, the binding rivets It being applied to hold the parts in their assembled position with the rivet passing through the holes H in the guides l3 and through the yoke of the C-shaped field magnet l0. s

The armature i9 is made up of a plurality of laminations, two of which extend beyond the others to form an attachment 20 for a link II for connection to the mechanism to be acted upon. The laminations of the armature l9 are fastened together by-means of rivets 23 and 24. The rivet23 is flared flushed with the outer lamination of the armatureyand the rivet 24 is provided with washers 26 and 21 which extend a short distance beyond the faces of the external laminations of the armature It. The armature guides l3 are made of material of greater thickness than the washers 26 and 21 and are provided with slots 30 and 3| of such a width as to receive the washers 26 and 21 respectively of the armature. The outer ends 33 of the plates of the armature guides I! in which the slots 30 and II are formed are offset outwardly away from the armature so that when the armature i9 is assembled within the armature guides I3, the outer faces of the washers 26 and 21 will pass within the plate extensions 33 of the armature guides [3 in alignment with the slots 30 and ll of the guides i3. A pair of stop plates 35 having portions 36 contoured substantially to fit the stop washers 26 and 21 extend across the outer ends of the armature guide member 13 on the armature side of the extensions 33, the plates 35 being riveted or similarly attached to the opposite ends of the C-shaped field ID by means of rivets 31 which also pass through the cover plates 40 and 4|, preferably, suitably formed to straddle the projecting plates 33 on the outer ends of the armature guides Hi to aid in holding the guides in place. The cover plate 40 may be a part of a terminal support 43, or may be made similar to the cover plate 4| if the terminal support is not desired. The inner end of the armature may be provided with one or more copper coils 45 for creating a phase lag between the armature and field magnetic waves to prevent chattering when the solenoid is energized with alternating current.

Although certain details oi construction are here illustrated and described as forming .8 p rt of the embodiment in which my invention is incorporated, it is to be understood that I do not wish to be unduly limited thereto, my invention being applicable to variations from many or the details thus shown and described.

What I claim and desire to secure by Letters Patent is:

In a solenoid structure, an armature, a guide surrounding said armature and having a slot provided therein and said guide formed to allow sliding movement of said armature in said guide, a winding surrounding said guide, a projection on said armature extending from the side thereof into said slot but not through said slot and positioned to slide in said slot on movement of said armature in said guide, an offset portion of said guide near the end thereof offset in a direction outwardly from said armature, and a stop member inserted under said oiIset portion and positioned to act as a stop for limiting the sliding movement of said armature by contact of said projecting portion with said stop member.

MYRON W. BOWEN. 

